This paper presents an empirical investigation to identify and weight elongation factors promoting science and technology parks for development of the national innovation system. The study designs a questionnaire in Likert scale and determines the relative importance of seven groups of items including policy, financial resources of innovation, knowledge acquisition for innovation, upgrading innovation technology, knowledge distribution, human resources development and good and service production. Using some statistical observation, the study indicates that human resources development is the most important factor followed by financial resources and policy. In addition, the study has determined positive and meaningful relationships among all pairs of factors in development of national innovation system.